Firebreathing KV from Chelyabinsk

Flamethrower tanks were not a rarity in the Red Army. Work on chemical tanks began in the early 1930s. Initially, they were meant to deploy chemical weapons, but “universal” chemical tanks appeared soon after that. The first of them was the KhT-26, a vehicle on the T-26 tank chassis that could fire both poison substances and flame. As a result of trials, the flamethrower mode became the priority. The KhT-26 was succeeded by the KhT-130 based on the single turreted variant of the tank. The last variant was the KhT-133, the same vehicle but based on a T-26 with a conical turret and sloped turret platform sides. The last tanks were delivered in 1940 when the concept of a “universal” chemical tank had already died. The requirements for flamethrower tanks also changed.

The KV-8 formed by the end of November of 1941 alongside the KV-7.

The experience of using chemical tanks showed that the concept had many drawbacks. In addition to a short range of the flamethrower, a lack of main gun proved to be a problem. The flamethrower could be a secondary weapon, but not a primary one. Starting in 1940, development switched to tanks with flamethrowers in the hull and a cannon in the turret. There were several variants developed, but it ended up on the upper front hull. The gunpowder flamethrower developed by factory #174 by a group led by I.A. Aristo. The flamethrower was supposed to be installed in the T-34, KV, and T-50, but flamethrowers in the T-34 and KV-1 were incredibly rare in 1941. At this point work on flamethrowers split. The T-34 and KV-1 had their own approaches to the flamethrower.

A prototype was ready by the end of December of 1941.

100 mm D-10 vs 88 mm KwK 43

The Red Army took the threat of German anti-tank weapons very seriously, and the 88 mm Pak 43 remained a reference point for enemy anti-tank guns even after the war. In part, protection from this gun was listed as a requirement for post-war medium and heavy tanks. These requirements allowed me to compare the penetration of the German 88 mm Pak 43 and Soviet D-25T. Turns out, a similar analysis was done using the 100 mm D-10T gun.

This data shows PTP limit (the velocity at which the rear of the plate remains intact) curves of the 88 mm gun against medium hardness cast armour. It is visualized in two ways. The first has impact angle as the X axis and impact velocity as the Y axis. A curve is drawn for different armour thicknesses. The second graph shows the same data, but with the thickness as the X axis and curves drawn for each impact angle.

From these graphs, we see that the 88 mm Pak 43 is a powerful weapon indeed. At point blank range, it can penetrate 120 mm of armour sloped at 60 degrees (incidentally, the armour thickness proposed for modernized IS-2 tanks in 1944). The IS-4's armour protection (140 mm at 60 degrees frontally, 160 mm at 30 degrees on the sides) also offers good but not perfect protection against damage from the 88 mm Pak 43.

At 1000 meters and a velocity of about 900 m/s, the gun can still penetrate 100 mm at 60 degrees or 130 mm at 50 degrees. These look very similar to requirements for the T-54's armour, making it very clear what opponent this tank was designed to fight. 

This data shows the same thing but for the 100 mm blunt nosed AP shell. The penetration is considerably higher. Rather than 120 mm at 60 degrees, the gun penetrates a hair over 160. At 50 degrees, this shell penetrates 180 mm of armour compared to the 88's 150. Unfortunately the graph for the Pak 43 does not show penetration at 30 degrees at point blank range, but extrapolation shows that it penetrated less than 200 mm of armour while the D-10 would penetrate slightly more.

At 1000 meters and a velocity of about 800 m/s the gun penetrates 140 mm of armour at 60 degrees and almost 160 mm at 50 degrees, again keeping a slight edge on the 88. At 30 degrees the gun penetrates 180 mm of armour, making it capable of penetrating both the front turret or the front hull of a Tiger II at ranges where the Tiger II can penetrated it back.

And finally, the 100 mm sharp-tipped AP shell. This shell is not as good as the blunt-tipped AP (same thing is observed with the 122 mm D-25's ammunition as well). At point blank range the gun penetrates 130 mm of armour at 60 degrees, a hair more than the 88 mm Pak 43. At 1000 meters penetration drops to almost 120 mm at 60 degrees or 140 at 50 degrees, still keeping just ahead of the Pak 43. At 30 degrees the gun penetrates less than 180 mm of armour, making it a little riskier to fight a King Tiger head on. 

When it comes to the Panther, a more realistic opponent, the 100 mm gun can defeat it at a great range. The upper front plate (85 mm at 55 degrees) can be penetrated at a velocity of about 600 m/s with the sharp tipped shell (a range of over 3 kilometers) and at even greater ranges by the blunt tipped shell.

RGAE F.8734 Op.8 D.249 L.1-6 via Yevgeniy Narimanov and Artem Belyakov.

A Tank from a Former Ally

The T-34 was a mystery for the USSR’s allies for most of WWII. A sample of the legendary tank was only sent abroad in 1943, but information about an improved variant with a 3-man turret and an 85 mm gun became available soon after. Very little was known about this tank up until the spring of 1945, and with the end of the war the remote possibility of getting a sample vanished altogether. However, the odds of seeing this tank again increased with time. The Korean War broke out on June 25th, 1950. The Korean People’s Army (KPA) received aid from the USSR, which included T-34-85 tanks.

Old tanks in a new war

According to American sources, the North Koreans crossed the border on June 25th, 1950, with one armoured division consisting of three regiments numbering 160 T-34-85 tanks in total. The 16th and 17th Armoured Brigades joined them by September, and in November the 17th Mechanized Division with 41 tanks and 41st, 45th, and 46th Tank Regiments with 10 tanks each and the 43rd Mechanized Regiment with 13 tanks also crossed the border. According to the Americans, the North Koreans initially built up a force of 320 tanks in total, which was later reinforced by another 250 tanks.

A T-34-85 tank and a column of motorcyclists belonging to the Korean People’s Army.

Shopping List

 "Attachment to instructions of department 1b, 8th Infantry Division, June 20th, 1941

List of military equipment that must be captured for use. Items marked with a + are especially important.

Guns and equipment:

• 7.62 mm pistols
• 7.62 mm rifles (three line)
• +automatic rifles
• Maxim machine guns
• 51 mm mortars
• +45 mm guns model 1936
• 37 mm Rheinmetall anti-tank guns
• +any gun larger than 100 mm in caliber (especially cannons)

The Most American Sherman

A number of different fates could befall a Sherman tank. They fought in the deserts of Africa, the jungles of South-East Asia, the steppes of the Soviet Union. Tanks build at American factories could end up anywhere and fight with any crew, with one exception. The Medium Tank M4A3 with a Ford GAA engine was almost guaranteed to be crewed by Americans. Let us tell the story of the Sherman tank that the American preferred to keep to themselves.

Ford vs. Wright

The American automotive industry made a large contribution to victory in WWII. As one of the largest automotive manufacturers, Ford couldn’t avoid taking part. The company began working on an analogue to the British Rolls-Royce Merlin in 1940. The Air Force rejected this V-12 engine, but soon it found a home on land. Like the Merlin, a version of which was used on Cromwell tanks, the new Ford engine could be used on American medium tanks.

Ford GAA engine, Saumur tank museum.

HPZ’s Unlucky First

August 20th, 1920, can be considered the starting point for Soviet tank building. It progressed pretty quickly. By 1921, the Red Army already had classifications for its new tanks. Captured British Mark V tanks were assigned to category B, or breakthrough tanks. Mk.A Whippet and Mk.B Hornet tanks were assigned to category S, manoeuvre tanks. Finally French Renault FT tanks and the Russian Renault were assigned to category M, support tanks. For obvious reasons, development of category B tanks was not expected until the future. They were too heavy and complicated for the nascent Soviet industry. A decision was made to focus on manoeuvre and support tanks. Work was conducted by the GUVP (Main Directorate of Military Industry) headed by Senior Engineer Shukalov as of August 1921. Until 1924, this department largely stood idle, since no decision was reached on who would build these tanks and how. There were various ideas discussed, including letting factories design their own tanks. There was already one such instance, although the development of the Teplokhod AN at the Izhora factory was never completed.

Final iteration of the 16 ton manoeuvre tank developed by the GUVP. This was a predecessor of the T-12 tank.

A Soviet Look at French Cavalry

It just so happened that Soviet tank building grew out of the French school. Renault FT light tanks captured in the spring of 1919 happened to be the most appropriate type for production in Soviet Russia. That resulted in the Russian Renault, the first Soviet tank produced in series. The MS-1 tank followed. This was a whole new tank from a technical point of view, but performed a similar role to the Russian Renault. There is nothing strange about this, as French tank building was still the object of imitation in many countries. The Red Army continued to watch what was happening in France even in the late 1920s. Khalepskiy’s commission unsuccessfully tried to buy a French Renault NC tank, and traces of this tank can be seen in the design of the T-19 tank, the unsuccessful replacement for the MS-1. This is where the concept of a 3-man tank with a 1-man turret comes from. Priorities changed after that.

Three Pz.Kpfw.35 S (f) tanks were captured more or less intact in the end of January of 1942 with the Panzerzug 27.

Super T-50

 "Memo

Out of the two T-50 tanks developed by factory #174 and the Kirov factory, the one developed by factory #174 was accepted into service.

The Kirov factory proposes increasing the thickness of the armour on its tank to 60 mm and installing a 76 mm gun. This should increase the weight to 25.5 tons. The top speed will be 40 kph with a 300 hp V-4 engine.

Factory #183 reviewed the T-34 tank and is proposing building it with a torsion bar suspension. With 45 mm thick armour it would weigh 25 tons, or 28 tons with 60 mm of armour. It would be armed with a 76 mm gun and have a top speed of 50 kph with a 600 hp V-2K engine.

Comparing the two tanks, one can see that they have identical armour and armament. The difference in weight between the two tanks is not great. The T-34 is faster and has a greater power to weight ratio: 21.4 hp/ton vs 11.7 hp/ton. 

It is senseless to have two tanks with the same purpose in production at the same time. This will make issues of usage and spare parts more complicated. The factory #174 T-50 tank already exists as a means of infantry support.

I consider it impractical to develop and produce a T-50 tank with 60 mm of armour, since:

1. The T-34 tank with a torsion bar suspension has better characteristics.
2. It's senseless to introduce additional types of vehicles into service.
3. This work will distract the Kirov factory from its primary work.

GABTU Chief, Lieutenant General of the Tank Forces, Fedorenko"

Via Yuri Pasholok

Shermans in Mud

The Medium Tank M4 showed itself as an effective weapon over the course of decades of service. Tanks from the Sherman family successfully fought in every corner of the world in WW2 and after. However, these tanks still had a number of design drawbacks that American engineers had to fight to solve while the tank was already in production. One of these drawbacks was poor mobility in soft soil.

Attachments of every kind

One of the reasons why the Sherman’s off-road mobility left much to be desired was the high ground pressure. Even the prototype Medium Tank T6 didn’t have particularly wide tracks, and every subsequent variant of the Sherman became heavier and heavier. Ground pressure increased along with weight.

A Medium Tank M4A1 that sank in mud, Miturno, Italy, 1944. The high weight and narrow tracks of this vehicle meant that off-road mobility was low.

Widespread Welding

"Order of the People's Commissar of Tank Production of the USSR #200s
Moscow
March 28th, 1943

The meeting gathered in response to my order given on December 18th, 1942 in Nizniy Tagil at factory #183 on the issue of widespread introduction of automatic welding explored the issues raised and came to the following conclusions regarding automatic welding.